Make mailto links in Iceweasel (Firefox) launch Icedove (Thunderbird) instead of Evolution
Alternative title: Change default email application in Gnome shell
I'm running Gnome 3.4.1 (Debian Testing -- Wheezy). When clicking mailto links in Iceweasel, Chromium and Epiphany, the Evolution Setup Assistant dialog would pop up. Problem is I'm already using Icedove (e.g. Thunderbird) as my MUA (email client) and want that as my default application for email related tasks (such as when I click a mailto link).
One way to approach this with application specific hacks. For instance mucking with about:config and mimeTypes.rdf for Iceweasel (e.g. Firefox). The proper way is to tell Gnome that Icedove is the default email client and mailto link handler. Problem is that the option to set default application is difficult to find in Gnome Shell. I believe it used to be more prominently displayed, but now hidden in System Settings (gnome-control-center) under "System Info". Seems confusing because "System Info" sounds like a place you would go to get information about the system (which is what it mostly does), not choose default applications.